In the production and packaging of baked work products, for example, cookies, crackers, wafers and the like, the dough of the work products is distributed over and deposited on a plurality of parallel conveyors which move the work products for baking through an oven. Once carried through the ovens, the now baked work products may be further processed, for example, so that the work products are enrobed or iced and used to form cookie or cracker sandwiches. The work products are then typically moved in series along at least one, and oftentimes several, parallel conveyor lines for wrapping and packaging.
In known fashion, the work products can be carried in a low shingle, i.e., the leading edge of each work product is rested on the trailing edge of the work product immediately ahead of it as the work products move downstream along the path of travel. The work products can be kept in a low shingle until they arrive at a packaging machine where they are formed into a row of generally aligned and vertically edge standing work products positioned adjacent one another, forming a continuous line along a portion of the path of travel. However, in order to package the work products they must first be formed into separate groups of a consistent and uniform size. These grouped work products can then either be packaged in a thermoplastic packaging film formed as a tube about the work products, or they can be moved into a tray or other package in which the work products are sealed and transported for sale.
Not only will the aligned row of edge standing work products be formed into separate groups, however, but this is typically at production rates which may exceed several hundred work products per minute, for example 350 to 450 work products per minute delivered from the baking oven conveyor lines to the packaging line. Thus, what is needed is a method and apparatus of quickly and efficiently forming separate groups of work products for packaging which will not damage the work products while so doing, and which will be able to match the product flow rates upstream on the production line without otherwise slowing or impeding the production flow of the work products at the group forming and wrapping stage.
An early example of an apparatus used to form groups of work products is disclosed in U.S. Pat. No. 4,235,329 to Crawford, et al., issued Nov. 25, 1980. Crawford, et al. teach a series of adjacent work products being moved along a path of travel on the feed conveyor of a packaging machine in which a portion of the feed conveyor is upwardly displaceable in timed relationship with the movement of the work products along the path of travel so that the downstream work products are separated from the generally continuous row of upstream work products. Thereafter, one of a series of spaced lugs is moved into position for pushing the now separated group of work products along the feed conveyor toward an accumulating device, the end of the feed conveyor adjacent the accumulating device being vertically displaceable in timed relationship with the movement of the work products along the path of travel for placing the groups of work products onto separate levels of the accumulating device. The apparatus of Crawford, et al., however, appears to be best suited for work products which are laying along their longest rectilinear dimension, and does not appear to be well suited for dealing with a series of aligned and vertical edge standing work products being delivered from a high speed production line. Moreover, it does not appear that the device of Crawford, et al. is well suited for automatically adjusting the spacing between groups of work products, as well as setting the dwell, i.e., delay, in which the group of work products is formed for automatically sizing the groups of work products as they are moved along the path of travel.
Another approach to forming separate groups of work products from a row of work products is disclosed in U.S. Pat. No. 4,098,392 to Greene, issued Jul. 4, 1978, and in U.S. Pat. No. 5,095,684 to Walker, et al., issued Mar. 17, 1992. In the patent to Greene a series of juxtaposed separator blades are inserted downwardly into a line of edge standing work products, in this instance potato chips, whereupon the juxtaposed separator blades are moved apart from one another for forming a gap between the work products, thus forming groups of work products for packaging. The device of Greene accomplishes this task by using a guide track which functions as a cam for directing the juxtaposed blades into the row of work products and a second mechanical camming mechanism which acts to move the upstream separator blade away from the downstream separator blade as both blades move with respect to one another along the path of travel.
In the patent to Walker, et al., a series of work products are moved toward a pair of separator blades located near a cookie tray loading station the work products being in an aligned edge standing relationship with one another on a moving surface conveyor. As with the device of Greene, the device of Walker, et al. uses a pair of juxtaposed separator blades which are inserted downwardly into the row of work products, the separator blades then being mechanically cammed apart from one another forming a gap in the row of work products, and thus forming a group of work products downstream of the separator blades for being loaded into in a cookie tray.
Both the patents to Greene and to Walker, et al., however, rely on fixed mechanical relationship for forming the groups of work products as the work products progress along the path of travel. Moreover, and in a fashion similar to the device of Crawford, et al., the devices of Greene and to Walker, et al. are not designed for forming groups of work product, i.e., slugs of work products, which may vary, or may be automatically varied in size during processing. Also, the devices of Greene and Walker. et al. rely solely on mechanical mechanisms to move a pair of juxtaposed separator blades apart for forming a gap in the row of work products to create a group or slug of work products, all of the slugs of work products being of fixed and constant dimension without the ability to automatically vary the size of the slug from group to group of work products in accordance with the packaging needs of the processing operation.
Thus, what is needed, but seemingly unavailable in the art, is a method and apparatus for forming groups or slugs of work products from a generally continuous row of vertical edge standing and aligned work products being moved at a high rate of speed along a packaging line which also allows for the automatic sizing of the groups of work products without the need to stop the production line in order to reset the sizing mechanism forming the groups of work products. What is also needed, but seemingly unavailable in the art, is a method and apparatus of forming groups of work products which can be used with any typed of closely aligned work products, to include not only baked foodstuffs, but also other work products capable of being produced in high volume, high speed, manufacturing operations with the requirement of forming groups of work products for packaging and/or further processing. Therefore, what is needed is a universal method and apparatus for forming groups of work products from a continuous and aligned row of edge standing work products regardless of the type of work products being processed, and adapted to work with high speed packaging production lines.